Acid is sort of like weed in terms of having a lot of different 'strains' for lack of a better word. Of course, LSD is LSD, but anyone who has done acid from multiple batches will tell you that in practice different batches seem to have a tendency toward different effects. I've noted three particular types of LSD in terms of the feeling (well, even more really, but three I have the most experience with), one is the stuff that was coming out of Netherlands (Hofmann on a bike print), the other is another type from Europe (was on hotlips / rolling stones prints), and another is the stuff from USA like GDF white on white and phish family too was pretty much the same. We could argue about what makes them different, maybe they are not even all LSD but different ergotamines being passed off as it, but that is irrelevant for the sake of discussion. Definitely purity of crystal comes into play as well, for example I've seen crystal LSD like what was on the Hofmann prints and it is brown tarry goo looking shit, whereas GDF LSD is white powder/crystal and undoubtedly purer (if you use the purity grading scale that some do, you would say that GDF LSD is typically needlepoint or white fluff, which are the two highest grades).

LSD is also notable for having a very large selection of effects that a given trip can pull from, and the effects play off each other in complex fashions, so no two trips are really exactly the same, though the effects drawn from do seem to kind of correlate with the batch of LSD. The Hofmann on a bike LSD was notable for having a very quick come up (like 20 minutes to effects), it had more of a club drug feeling to it, kind of speedy, reminiscent of a drug like MDMA, with some spirituality but more of a party drug vibe to it, also notable for having a burned out feeling afterwards, and for not seeming to build tolerance as much as other LSD. GDF style LSD tends to build tolerance very rapidly as would be expected with LSD, it has a longer come up (like an hour to onset), is mellower in the sense that it doesn't feel like a club drug, but has much more of a spiritual feeling to it, it feels very clean and refreshing without a burned out feeling. The hotlips LSD was characterized as being very mental and kind of dissociating into your own mind, kind of more internal analytical LSD without being very visual. I've had acid from several other batches but have much less experience with them.

So as you can see it can be really hard to describe exactly what LSD is like, you have the "type" of acid, how much you take of it, the effects you happen to get from it, how the effects play off each other, set and setting, it's an extraordinarily variable drug which is one of the things that makes it so awesome. Some drugs feel very scripted, by which I mean taking them is similar to like watching a movie, it's always the same every time you watch it, it has entertainment value sure, but you know what to expect. I liken LSD more to being a set of paints (the effects) that are made available to you in some combination, and the experience is the painting that you make with those effects, and between two different trips the painting could be very different, unlike the movie of some drugs which is always the same.

I will break down some of the notable potential effects I suppose, though some of them are very rare (I've used LSD hundreds of times, and some of the effects I've only had once).

Synesthesia

Is a very rare potential effect of LSD which I've had once from it. This is the merging of various senses, such that you perceive one sense (such as sound) as if it were a different sense (sight). When I experienced this, it was as music notes popping out of my speakers during the playing of music, and kind of floating around them moving around to the sound, sort of like you could imagine in a game like The Sims. I think what may have happened is I had that image in my visuospatial sketchpad and then confabulated that I had it from my real visual intake in memory, but it was perceived as having actually seen that happening. This is kind of common with dissociating drugs, where you perceive your visuospatial sketchpad as if it were your real visual intake, with LSD this isn't very common, but I think the profound (as compared to standard) visuals of LSD are dissociated perceptions in the same fashion, but coupled with immediate confabulation such that it becomes the memory of external reality despite originating in the internal visuospatial sketchpad (augmenting external visual perception internally, then remembering the external input as if it had been the internal construction).

Ego Death

Is also quite rare, I've only had it once, though once I was on the verge of it but decided I didn't want to experience it at that time and had enough control to not do it (but I didn't fight it, I just didn't select to do it, fighting it is a bad idea). This can be described as a feeling of merging with God, which is how I initially perceived it. Today I would use less religious words to describe it though, it's the feeling that there is a CPU that runs the entire universe, and that you are a process being run by that CPU, just as everything else is, but during ego death you kind of feel like you gain awareness that you are not the process in ultimate reality but rather are the CPU manifesting itself through the process of your ego. This actually takes the fear of death away from some people, particularly if they actually accept it as valid rather than a drug induced state of being (as some do), and is a valid treatment for end of life anxiety.

When I had ego death it was pretty much I started seeing the air twist into transparent double helix structures, and this just kept happening at an increasing rate, and then things started to dissolve into double helix structures, including myself, and the particles started to separate from each other as if gaseous, and then everything blew away into eternal whiteness, at this point I believe I was dissociated into visuospatial sketchpad (profound visual of LSD seems to be dissociating into visuospatial sketchpad like NMDA antagonists), but in any case I had the perception of no longer existing in that I felt like I was everywhere in space and time, like I was everything so the I that I traditionally thought of no longer existed as a discrete unit separate from the continuity of existence, I was no longer a process but I was the CPU that all processes were run from, I merged with God.

Those are just two effects that are bad ass but like I said quite rare, talking like 1:300 or so here.

Once when I was tripping I had vivid episodic memory recall of a negative event in my life (a fairly common effect, especially on the rolling stones / hotlips type acid, where you drift off into vivid recall of past events, often more vivid than you even realized you had the ability to recall, often this is coupled with getting into kind of strange/bizarre postures IRL reminiscent of catatonic schizophrenia), and I felt really sad about this (amplified emotions are common on LSD), but then I came back into reality (from the dissociated episodic memory recall state), and I perceived a portal into another dimension (possibly in my visuospatial sketchpad augmenting reality and then confabulated as in reality), and good emotions were coming from the portal healing me (really I was experiencing rapidly fluctuating emotions, another common effect of LSD), and I attributed this as God opening a portal into another dimension to send me emotions to heal me (attributing inexplicable things to God / thinking about God in general is a common effect of LSD).

So I had many isolated effects of LSD here, but they all played off each other to tell a story (God healed me from the bad things that happened by opening a portal into another dimension and sending me good emotions). Very complex stories can be constructed around the effects of LSD, which makes it really hard to describe LSD in a sense....

other effects of LSD

High definition vision

This is pretty much characteristic of LSD, though I have had somewhat disappointing one off batches of LSD that didn't really have it much and focused more on adding visual effects to reality (tracers, patterning, etc). I like tracers and patterning, but LSD that doesn't give me high definition vision is disappointing. Pretty much you have a hyper awareness of deviations in shades and colors, hyper awareness of motion (you are amazed watching the trees blow in the wind because you get all of the motion from every single moving part of it and perceive it at once, it's like your range of focus increases), hyper awareness of spatial relationships (space seems to be an object of its own and very notable rather than being characterized more as the lack of anything), hyper awareness of fine details that your brain normally seems to kind of blend together into a big picture, things seem to really "pop".

High definition audio

Also pretty much characteristic of LSD, music sounds absolutely fucking amazing better than any other drug (it's similar to marijuana in this sense, and actually has a significant synergy with marijuana in general the effects really compliment each other well). Instead of all of the sounds kind of blending together into one stream of music they really stick out as independent threads in a sense, kind of the audio equivalent of the visual detail awareness thing.

like I could go on and on though because there are like two dozen+ different effects associated with LSD, but the thing is you will experience some subset of them, and they will play off each other to kind of make complex effects/experiences, it's impossible to really capture LSD in text, it's like asking what a painting is like before it has been painted, the best you can do is describe the paints and maybe a couple of paintings others have made.